package com.demo.sell.service.impl;

import com.demo.sell.converter.OrderMaster2OrderDTOConverter;
import com.demo.sell.dataobject.OrderDetail;
import com.demo.sell.dataobject.OrderMaster;
import com.demo.sell.dataobject.ProductInfo;
import com.demo.sell.dto.CartDTO;
import com.demo.sell.dto.OrderDTO;
import com.demo.sell.enums.OrderStatusEnum;
import com.demo.sell.enums.PayStatusEnum;
import com.demo.sell.enums.ResultEnum;
import com.demo.sell.exception.SellException;
import com.demo.sell.repository.OrderDetailRepository;
import com.demo.sell.repository.OrderMasterRepository;
import com.demo.sell.repository.ProductInfoRepository;
import com.demo.sell.service.OrderService;
import com.demo.sell.service.ProductService;
import com.demo.sell.utils.KeyUtil;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageImpl;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;

import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

@Service
@Slf4j
public class OrderServiceImpl implements OrderService {

    @Autowired
    private ProductService productService;

    @Autowired
    private OrderDetailRepository orderDetailRepository;

    @Autowired
    private OrderMasterRepository orderMasterRepository;

    /**
     * 创建订单
     * @param orderDTO
     * @return
     */
    @Override
    @Transactional
    public OrderDTO create(OrderDTO orderDTO) {

        String orderId = KeyUtil.genUniqueKey();
        BigDecimal orderAmount = new BigDecimal(BigInteger.ZERO);

//        List<CartDTO> cartDTOList = new ArrayList<>();

        //1. 查询商品（数量，价格）
        for(OrderDetail orderDetail :orderDTO.getOrderDetailList()){
            ProductInfo productInfo = productService.findOne(orderDetail.getProductId());
            if(productInfo == null){
                throw new SellException(ResultEnum.PRODUCT_NOT_EXIST);
            }

            //2. 计算订单总价
            orderAmount = productInfo.getProductPrice()
                    .multiply(new BigDecimal(orderDetail.getProductQuantity()))
                    .add(orderAmount) ;

            //订单详情入库
            BeanUtils.copyProperties(productInfo,orderDetail);
            orderDetail.setDetailId(KeyUtil.genUniqueKey());
            orderDetail.setOrderId(orderId);
            orderDetailRepository.save(orderDetail);

//            CartDTO cartDTO = new CartDTO(orderDetail.getProductId(),orderDetail.getProductQuantity());
//            cartDTOList.add(cartDTO);

        }

        //3. 写入订单数据库 (orderMaster 和 orderDetail)
        OrderMaster orderMaster = new OrderMaster();
        BeanUtils.copyProperties(orderDTO,orderMaster);
        orderMaster.setOrderId(orderId);
        orderMaster.setOrderAmount(orderAmount);
        orderMaster.setOrderStatus(OrderStatusEnum.NEW.getCode());
        orderMaster.setPayStatus(PayStatusEnum.WAIT.getCode());
        orderMasterRepository.save(orderMaster);

        //4. 如果下单成功，扣库存
        List<CartDTO> cartDTOList =orderDTO.getOrderDetailList()
                .stream().map(e -> new CartDTO(e.getProductId(),e.getProductQuantity()))
                .collect(Collectors.toList());
        productService.decreaseStock(cartDTOList);

        orderDTO.setOrderId(orderId);
        return orderDTO;
    }

    /**
     * 查询订单
     * @param orderId
     * @return
     */
    @Override
    public OrderDTO findOne(String orderId) {

        OrderMaster orderMaster = orderMasterRepository.findOne(orderId);
        if(orderMaster ==  null){
            throw  new SellException(ResultEnum.ORDER_NOT_EXIST);
        }

       List<OrderDetail> orderDetailList =  orderDetailRepository.findByOrderId(orderId);
        if(CollectionUtils.isEmpty(orderDetailList)){
            throw  new SellException(ResultEnum.ORDERDETAIL_NOT_EXIST);
        }

        OrderDTO orderDTO = new OrderDTO();
        BeanUtils.copyProperties(orderMaster,orderDTO);
        orderDTO.setOrderDetailList(orderDetailList);
        return orderDTO;
    }

    /**
     * 获取订单列表
     * @param buyerOpenid
     * @param pageable
     * @return
     */
    @Override
    public Page<OrderDTO> findList(String buyerOpenid, Pageable pageable) {
        Page<OrderMaster> orderMasterList = orderMasterRepository.findByBuyerOpenid(buyerOpenid,pageable);
        List<OrderDTO> orderDTOList = OrderMaster2OrderDTOConverter.convert(orderMasterList.getContent());
        Page<OrderDTO> orderDTOPage = new PageImpl<OrderDTO>(orderDTOList,pageable,orderMasterList.getTotalElements());
        return orderDTOPage;
    }

    @Override
    @Transactional
    public OrderDTO cancel(OrderDTO orderDTO) {

        OrderMaster orderMaster = new OrderMaster();


        //判断订单状态
        if(!orderDTO.getOrderStatus().equals(OrderStatusEnum.NEW.getCode())){
            log.error("[取消订单]  订单状态不正确， orderId={}, orderStatus={}",orderDTO.getOrderId(),orderDTO.getOrderStatus());
            throw new SellException(ResultEnum.ORDER_STATUS_ERROR);
        }
        //修改订单状态
        orderDTO.setOrderStatus(OrderStatusEnum.CANCEL.getCode());
        BeanUtils.copyProperties(orderDTO,orderMaster);
        OrderMaster updateResult = orderMasterRepository.save(orderMaster);
        if(updateResult == null){
            log.error("[取消订单] 更新失败 , orderMaster={}",orderMaster );
            throw new SellException(ResultEnum.ORDER_UPDATE_FAIL);
        }

        //返回库存
        if(CollectionUtils.isEmpty(orderDTO.getOrderDetailList())){
            log.error("[取消订单] 订单中无商品详情，orderDTO={}",orderDTO);
            throw new SellException(ResultEnum.ORDER_DETAIL_EMPTY);
        }

        List<CartDTO> cartDTOList = orderDTO.getOrderDetailList().stream().map(e -> new CartDTO(e.getProductId(),e.getProductQuantity())).collect(Collectors.toList());
        productService.increaseStock(cartDTOList);

        //如果已支付，需要退款
        if(orderDTO.getPayStatus().equals(PayStatusEnum.SUCCESS.getCode())){
            //TODO
        }

        return orderDTO;
    }

    @Override
    @Transactional
    public OrderDTO finish(OrderDTO orderDTO) {

        //判断订单状态
        if(!orderDTO.getOrderStatus().equals(OrderStatusEnum.NEW.getCode())){
            log.error("[完结订单] 订单状态不正确, orderId={},orderStatus={}", orderDTO.getOrderId(),orderDTO.getOrderStatus());
            throw  new SellException(ResultEnum.ORDER_STATUS_ERROR);
        }

        //修改订单状态
        orderDTO.setOrderStatus(OrderStatusEnum.FINISHED.getCode());
        OrderMaster orderMaster = new OrderMaster();
        BeanUtils.copyProperties(orderDTO,orderMaster);
        OrderMaster updateResult = orderMasterRepository.save(orderMaster);
        if(updateResult == null){
            log.error("[完结订单] 更新失败 , orderMaster={}",orderMaster );
            throw new SellException(ResultEnum.ORDER_UPDATE_FAIL);
        }

        return orderDTO;
    }

    @Override
    @Transactional
    public OrderDTO paid(OrderDTO orderDTO) {
        //判断订单状态
        //判断订单状态
        if(!orderDTO.getOrderStatus().equals(OrderStatusEnum.NEW.getCode())){
            log.error("[订单支付完成] 订单状态不正确, orderId={},orderStatus={}", orderDTO.getOrderId(),orderDTO.getOrderStatus());
            throw  new SellException(ResultEnum.ORDER_STATUS_ERROR);
        }

        //判断支付状态
        if(!orderDTO.getPayStatus().equals(PayStatusEnum.WAIT.getCode())){
            log.error("[订单支付完成] 订单状态不正确, orderDTO{}", orderDTO);
        }

        //修改支付状态
        orderDTO.setPayStatus(PayStatusEnum.SUCCESS.getCode());
        OrderMaster orderMaster = new OrderMaster();
        BeanUtils.copyProperties(orderDTO,orderMaster);
        OrderMaster updateResult = orderMasterRepository.save(orderMaster);
        if(updateResult == null){
            log.error("[订单支付完成] 更新失败 , orderMaster={}",orderMaster );
            throw new SellException(ResultEnum.ORDER_UPDATE_FAIL);
        }

        return orderDTO;
    }
}
